Is this something people grow out of?
No. It's unlikely anyway. If it's a very recent thing for him where he just wants to experiment, then maybe, but if he's always been like this then it's likely he'll always be that way. Sexual fetishes and fantasies are really ingrained. I don't think it's unusual that when men can't get this need in a relationship they will pay a woman to do it to them, especially if they have a strong need for it. If it is a very strong need, which you may not find out about until later, then yes, a lot of your sex life might be dominated by his fantasy and he will get more and more bored with 'vanilla' which is what he might be ok putting up with at the start of the relationship, mainly to please you. They might eventually find any sex that does not involve BDSM to be boring and unfullfullfilling, after the spark has worn off, and you will be left with enacting things that do nothing for you sexually. Sex will involve a lot of acting for you, and I don't think that acting will be something he'll be happy with longterm because he knows it's not real.
People will have different reasons why they're into BDSM, but an often ignored component is misogyny and sexism which they've absorbed in their upbringing or society. Part of the reason why men like a woman dominating them is because they're into humiliation....and they can think of nothing more utterly humiliating than being dominated by a woman . For them, it's against the natural order of things which involves men being dominant over a woman, and not something a male should naturally aspire to, as women are of a lower status. Not good.
me choosing his meal for him and making him slip an embarrassing word into a conversation with a friend. Things like that aren't going to faze me
Right, so it's already started to leak into 'real life'. I really wish the best for you, but it wouldn't surprise me if this continues to grow. His sexual kinks should not be starting to influence what you do out of the bedroom especially if you are not that way inclined, but they already are. It may not faze you now, but it blurres the boundaries between fantasy and reality and that's exactly what men who are heavily into this stuff want. They don't just want a situation where they're dominated inside the bedroom or house - they want to have a relationship where they entire relationship revolves around their turn-on and he might become displeased if you don't agree to play his games with him. I might be getting my terms mixed up here, but I believe that people call this dominating from the bottom, or something like that. It's a situation where you are led to believe you think you are in control of all of this, that it's something that benefits you, whereas it's the 'bottom' (submissive) who's actually calling all the shots, often because they're in a relationship that is not suited to their needs.
I know I paint a bleak picture here and I hope I'm wrong about all this, but you really need to sit yourself down and ask yourself if you will be entertained or happy to pick out his meal for him in a few years' time? Is that the kind of relationship you really want?? 