No, a diplomatic passport is for diplomats and other government personnel to use in an official capacity. I had one because the first time I came to Thailand, I was under the State Department.
I don’t think customs agents are authorized to hand out passports. 
Put a travel date that is very soon, and they try to make sure you have your passport on time. If you don’t put a travel date, and are just getting it to have “just in case,” or for secure ID, it gets delayed.
I got my first passport at age nine, because we went to the USSR just after my 10th birthday. My parents renewed it when it expired, and I used it again when I was 18. I always renewed it every 10 years, because it seemed like a good thing to have, even though I had some I never traveled on, but did use as ID a few times, when I lost my driver’s license, or when I needed two picture IDs and didn’t have a student ID. When we suddenly needed passports to go to Mexico or Canada, I was very glad I had one at the ready. I traveled on my current one when my cousin decided to get married in Greece (her mother’s country of birth), so it was nice to have it ready.
It’s just a supplemental book of entrance visas. My father had one.
BTW: those stamps in your passport are actually visas, and they’re called “entrance” visas. What US citizens don’t need, ever, is exit visas. Some countries require citizens to get exit visas to be allowed to leave the country in the first place, and other countries require special paperwork in advance as entrance visas instead of immediately granting a tourist visa to anyone who shows up at the border.
US passport, renewed in 2013 for our China trip. My little then-5-year-old daughter also got hers that year, though hers is only good for 5 years, as I recall. We all also got pretty visas with the Great Wall on them for the trip.
And then, during the trip, the daughter we went over to adopt received her Chinese passport, which got a visa to travel to America in it. So we have one with a red cover too.
I’ve got one of each! It’s verra nice.
My sense of power is dampened somewhat by the fact that I have to file two sets of tax returns on the same income.
I have an active US passport which I just used to book a trip to Peru. I’m finally going to Machu Picchu! That was supposed to have been my celebratory trip upon graduating from medical school almost 8 years ago,
Until the early 1990s, it was the case in Thailand that foreigners residing here for more than 90 days had to get a tax-clearance certificate each and every time they wanted to leave the country. You had to shlep on down to the main tax office to get it. That did not affect me, as I was exempt from that in the 1980s as a US-government worker, and it was ended by the time I returned to Thailand. But I heard that was a huge hassle.