It's not gift-grabbing if you put a disclaimer on the card that says while well-wishes are appreciated and gifts are not necessary.
It's a shame that some people look at invites as folks begging for handouts. I know there are some people out there who are into the whole getting loot thing, but that's really rare. Planning a huge event ends up being pretty expensive—especially if you are doing it yourself and you involve food and alcohol. I'm not saying that justifies believing your guests have to bring gifts, but after all that work and money, the gifts come out in the noise.
I haven't had a baby shower, but I planned my own wedding. I invited a lot of extended family—some for the sake of parents. Quite a few did not come because they were far away and it wasn't a good time for them, but they still appreciated the invites (the invites were handmade which made it more special).
Then there were the long-distance relatives who actually did come. These included folks I didn't often see. They were really excited to come to see us marry, but a big reason they came was to see a large number of family members they'd not get the opportunity to see otherwise. It was kind of like a family reunion for some of my family, and it was really special to a lot of them. Our wedding was more than just an event...it was a party where everyone shared in our joy.
I wasn't initially interested in a baby shower, but my husband is. We will probably plan it the same way.