Do I need to buy a bunch of little pants?

Hannahbanana54

FTM, 31 weeks tomorrow and starting to worry about stuff that might be stupid (feel free to tell me if this question is stupid). 

We were so lucky to have been given 2 showers and receive a bunch of beautiful onesies for the baby (among other clothes). I'm wondering- since she'll be born in February, do I need to get a bunch of little pants for her to wear with the onesies or is this ridiculous since she'll be inside our house pretty much exclusively for the first few months? I also considered that maybe newborns need changed so much that If they wore pants, you'd spend all of your time taking off and putting on pants. I don't want her to be cold, but I didn't see a ton of 0-3 month old pants at Carter's or BRU when I went looking this weekend, leaving me to wonder whether (a) they don't carry a lot of them bc they're not really needed or (b) most of their 0-3 month pants were sold out because you really do need them.

Goodness, I am losing my marbles.