My understanding is that the traditional way to try to direct what people give you is to have your closest friends and relatives pass along your preferences by word of mouth.
I don’t know how close you are to your extended family, but it seems to me it’s not uncommon for distant relatives to ask the bride’s mother or other close relative what the couple can use. It would then be perfectly acceptable for your mother (grandmother, favorite aunt) to say something along the lines of, “Zsofia is registered at <Dept Store>, but what she and Joe can really use is money to remodel the master bath.” Your maid of honor and/or another close friend can spread the word among your social circle. The same procedure can be followed on your fiancé’s side.
Then, of course, when you send your thank you notes, you should let those who gave cash/checks know how you plan to use their gifts, and when the remodel is done it would be nice to send them pictures so they can see how the project they helped fund came out.
Unless you want your friends to think you’re a buffoon, don’t put anything about gifts in the invitation.
Guests who are interested in your preferences will inquire.
Zsofia, regardless of how established you are, I think if you wander around Crate & Barrel, or Macy’s or Home Depot or where ever you’ll find a reasonable number of things that you and the Mr would actually like to receive. Register for those, and make sure that there is a range of price points to accommodate every budget.
You don’t have to go crazy listing stuff you don’t want - just choose items that you do want - FWIW, I think the Home Depot will be pretty popular because a lot of people feel like wedding gifts are geared towards the bride, rather than the groom - Home Depot would probably ping with a lot of the younger, more egalitarian folks in the crowd.
And finally, to (sort of) address your actual question - I don’t believe that any stores return for cash anymore (none that I found); however, many will refund onto store gift cards, so if you choose Home Depot you’ll be able to swap stuff out for building supplies. Also, the vast majority of people just give cash now anyway - hubby and I were actually a bit sad that we didn’t get as many things on our registry and got cash instead because the presents were more fun to open. (Although the cash was lovely as well!)
Look, I’d love to say “no gifts, please! Just come!” but that’s just as rude as telling people what to get you. Anything you do that suggests you were expecting a present is rude as hell. I’m sure my mom will tell people that cash would be lovely, of course. Honestly I feel uncomfortable about any gifts people bring, as traditionally the idea is to set the young couple up in a household and we have all the household we can stand, you know? We plan to have a wedding website with all the stuff like which hotel we’ve reserved a block of rooms and all, so we thought we could prominently mention some of our favorite charities there without being pushy about it or offending anybody.
Another issue beyond the registry thing is that, yes, when people buy stuff it takes it off the registry… but sometimes people go and buy, say, the platter you registered for at an outlet store. Which is awesome, except you then have six Wedgwood platters and need to return something (which hopefully you’ll be able to do at the place you registered even if they didn’t buy it there) and then you have seven hundred bucks at Bed Bath and Beyond that you can’t necessarily use.
I was at a bridal shower once which was ridiculously huge (if you have 75 people at your shower you should have had two showers - we watched her open presents for two hours) and I’d gotten her a coffee maker from her registry at Target. She got, no lie, seven coffee makers. Three of them were the model specified on the registry, so either they didn’t tell the store to take it off the registry, they bought it somewhere else, or Target screwed up. So of course six will go back and you have this problem again.
If you register at someplace like Target, though, at least you can return for store credit and buy groceries and the stuff you’d normally spend money on anyway for the next year or whatever. Then the money you’d be spending on groceries can go to the bathroom fund. I’d register at Target and Lowes and maybe Amazon. Anything you need to return will be useful credit at any of those places.
(Although the cash was lovely as well!)