Baby shower gift question

If your mom or mil throws you a baby shower, and they buy the food decorations and everything. do you expect the people who come/ your FRIENDS to bring a gift or is their presence the present? I had a lot of people show up without a present. Is that normal? I thought the point of baby shower was to bless the mom with baby gifts for baby. Also these people wrote their name on the envelopes that were passed out for thank you cards. I find it a bit awkward because does that mean I'm sending them a thank you for their presence and my mil paid for them to eat? I find it kinda messed up since a lot of money was spend on preparing the shower, and we could have used it to buy things we needed instead.