I don’t care what anyone eats with their steak but I’m happy to argue about it. 
Rice does seem a little strange. Steak and potatoes. Steak and eggs. Steak sandwich. All get the checkmark.
Steak and spaghetti. Steak & raisins. Peanut steak risotto. Those seem weird, right?
Healthwise that may usually be true, depending on what particular nutrients your body particularly needs. But potatoes have downsides depending on how they’re prepared (e.g.- fried is not ideal, but tasty!). More importantly, rice is very amenable to having its nutritional value enhanced with added ingredients like being cooked in a healthy broth.
You have obviously not had steak with Wolfpup’s famous vegetable rice with porcini mushroom! 
I’d certainly never have steak with plain white rice.
I do this but with a little sesame oil mixed into the rice.
But if you think about it, how many people eat a plain baked potato? Comparing a baked potato with toppings to plain rice is apples to oranges.
It’s slightly odd to me, yes. I mean, if I went to a steakhouse and saw someone chowing down on a 20oz porterhouse with asparagus and plain white rice on the side, I would probably do a double take.
On the other hand, if I’m in some non-European or American joint, I’m sure I wouldn’t even notice.
So, yes, to me, it is weird. I’ve never seen somebody order rice at a steakhouse or any other American restaurant.
(Not to say that steak isn’t good with rice. It’s fine, but I would prefer that steak stir-fried and finished in a sauce if I’m having it with rice.)
A steak that I’d eat will have some juice or even gravy on it to mix with rice. Almost everything does. And people eat baked and mashed potatoes all the time without anything else on them or just some salt and butter that can be put on rice also. If you don’t want plain white rice because it’s dull that makes sense, but I’ve encountered people who refuse to eat rice, don’t want a dish they otherwise like if it’s served over rice, just saying “I don’t like rice”. That’s what I don’t understand.
Mostly I’m thinking of the old “boil in a bag” Uncle Bens, which was, yeah minute (actually a couple) rice. It’s what we had in the house growing up when we made rice at home. And I prefer jasmine and other “sticky” rice variants as an adult. But again, as I said with my dad, it’s what you prefer that is important.
I’m not of Asian descent nor culturally Asian, but I have always preferred rice to a boring potato. You can do so many more tasty things with it. And even moreso if you change to brown rice or one of the many other rices that aren’t just white short grain starchy.
I grew up with a large Mexican population nearby and rice and beans are standard with every such meal. Now that I live in a Caribbean / non-Mexican Latin American part of the USA, rice and beans still go with everything.
The OP is not at all weird = a statistical outlier absolutely. They may be weird = a statistical outlier locally in the ethnically homogenous culturally conservative frankly backwards bubble of post-communist Prague.
Well! It sure made my evening to see that many don’t find my choice of rice to be strange. That said:
To be honest, yes. On reflection, I realize that back home (IE, in North America) you probably wouldn’t be offered rice as a side to a steak, or even to much else that’s “typically American”. I simply saw what what was on the menu in the Czech Republic and discovered a combination that was to my liking, even if that combination was likely not the one that was originally intended. On that note:
Personally, I am happy to eat the steak grilled well and in its own juice, rather than with a sauce added. I can eat steak with pepper sauce, but wouldn’t add a gravy-like sauce. But to each their own. Your point does bring me back to why rice is offered as a side in Czech restaurants in the first place. It’s probably meant, not mainly for grilled meats, but for those prepared the traditional Czech way. Standard Czech cooking has a lot of pork-based dishes, as well as beef-based ones, but not grilled. The pork is roasted or cooked, and the beef typically cooked, in a brown or cream sauce of one kind or other. This is very typical. Goulash (beef, though can be made of pork or sausage), roast pork (the national dish, served with bread dumplings and steamed sauerkraut), beef cooked in cream sauce, and so on. Many of these are eaten with rice, which would serve the same purpose as dumplings - to pick up the sauce / gravy.
Maybe this is why my very good Mexican-American friend John seemed to be one of the few not to find my choice of steak and rice weird.
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Since you mention it, I’ve made goulash with lamb, originally because I had the meat and figured “why not?”, since then because it was good. Am I committing some type of heresy or would lamb be used as well on occasion?
That’s a good question. In the Czech Republic, it probably wouldn’t, because there is little consumption of lamb and mutton here. Unless someone got hold of a cut, and wanted to experiment. Venison and wild pig often end up in goulash.
That said, I wouldn’t be surprised at all if lamb goulash wasn’t made somewhere else. For that matter, what is called goulash here is a meat stew, whereas in Hungary, where the word originates, it means a kind of thick soup. There, a different word is used for what is called goulash outside Hungary.
I always prefer rice with steak, however it’s usually rice pilaf. Can’t say I eat white rice with anything but stir fry, though.
The word is pörkölt, and, yes, lamb or mutton may be used. When I was living in Hungary, it could be a little tricky finding that meat, but I did happen to live by one of the butchers in the city that did sell it. The Hungarian name would be birkapörkölt for mutton goulash and báránypörkölt for lamb goulash. I don’t remember ever coming across it in Budapest restaurants – I believe it is more of an Eastern Hungarian dish, though from reading up a bit, it seems the area southeast of Lake Balaton has some sheep, though Hungarians are not big sheep eaters these days. ETA: Oh, and in the Hortobágy area there are some racka sheep, known for their corkscrew horns. My Culinaria Hungary cookbook states that for centuries, Hungary was full of flocks of sheep, but these days lamb/mutton is more of a special occasion food. It does give two lamb recipes, one for mutton goulash (as ürügulyás) , which is a more soupy that pörkölt, and another for lamb cutlets. (As mentioned before, what is "goulash* outside of Hungary is generally what Hungarians call pörkölt, and their gúlyás is what sometimes goes by the name “goulash soup.”
To the OP: You do you. Rice is totally fine and awesome. Nobody has the right to tell you what to put in your own mouth/gullet.
I like fancy rices, particularly Persian tahdig or Colombian titoté rice with slowly caramelized coconut milk (both of which are gourmet dishes as much as a side). But most Asian rice dishes are good too.
But I like plain white Basmati or Jasmine too. Last week, I are a good steak with (easy to prepare) white Basmati rice, and did not consider this at all weird, though it might not be traditional.
I just looked at the menus of two of my favorite local restaurants. They both offer a grilled steak kebab dinner with basmati rice and vegetables on the side, no potato option offered. One calls itself a “Mediterranean grill” (the owner is Turkish/Cypriot) and the other is “Persian-Mediterranean”.
And a popular Colombian restaurant near me serves its steak with rice and beans.
Yes, of course a Mediterranean place is going to offer rice. That’s kinda standard. Especially with kebabs–either pita or rice. I’m imagining an American or European style steak – all in one piece. Rice would seem a little out-of-place to me for something like that. I’m not saying it wouldn’t be good – it’s just not standard in those cuisines. In others, it’s obviously normal. It’s not surprising in Prague the OP would get an askance look. It’s like all potatoes, flour, butter, and sour cream out there! Oh, and bacon. It’d be like asking for mashed potatoes with your chicken curry. (And, speaking from experience, that is actually pretty awesome!)
Absolutely. But I don’t think anyone is, not even in the OP’s story.
To me steak and mashed potatoes has this amazing flavor complement to each other. It’s a case where 2+2=5. OTOH I sort of feel the opposite with steak and rice, they clash just bit to me, not in a 2+2=3 way, but it is a disappointing complement compared to what it could be. That is unless I am making the steak a teriyaki or korean style.
I also took beefsteak to mean ‘a steak.’ Once you stir fry or skewer or pho it, it’s something else.
And it’s just rice, not a bowl of M&Ms. And there are exceptions like steak tampiqueña or teppanyaki which would be well accompanied by rice.
I assumed it meant steak. And while I enjoy rice, and might occasionally prefer it, in general fancy mashed potatoes are an awesome side, especially with steak.
A really good place might offer