Throwing a smaller party for 1/2 the people is half the stress. So the parents are just being tightwads. Just look at the invite. They want more gifts for less effort and cost. Rude and cheap.
Blunt.....to the point.....and the gospel truth.

Another poster summarized it as the b-day parents wanting to spend
HALF the money and get
TWICE the presents. Also an accurate description. It seems to me these mommies can do the math quite well. They have just never bothered to read an etiquette book.
DD had a "home" b-day party for her 1st and 2nd b-day. Her 1st was friends and family. (Actually, we'd just brought her home from Russia and I swear, I think she had about three 1st b-day parties.

) For her 2nd, we invited our friends and 7 of their toddler children to play at our home. Once she hit age 3, we've had a "BIG" b-day party every year, save the year we took her to WDW and even then she had a smaller b-day party when we got home.
In other words, I've done the venue b-day parties to death so I know how expensive, stressful and time-consuming they are. Yet I would NEVER in a million years "share" the party expense with another parent and expect....excuse me, DEMAND....that the guests my child didn't even have a hand in inviting bring equal gifts for BOTH b-day children. That's rude, tacky, cheap, and makes me look as if I was raised in a barn or at best, by wolves.
If I cannot afford to give DD a party without lowering myself to such a level, then I would simplify her party and have it at a less expensive venue or God forbid, at home.

At first, even though we had the party at a party place, I still knocked myself out. There was a lot to do. As time has passed, I have gotten better at finding places where I pretty much have to send out invitiations, bring the cake and prepare goody bags. And I could buy premade goody bags if I was really in a bind. DD's last party was a movie party and at the end of it, I handed over a Visa card to the party coordinator and was DONE. Lord love him......I know I did.

Stress? Not really. Cost? $15.00 per kid, plus cake, invitations, thank yous, goody bags and a few other goodies I kicked in. It didn't break the bank. Invite 5 kids to something like that and you're out $120 or so. DD invited a decent amount of kids, but that was completely within our control. My point is, venue parties don't have to be stressful, ungodly costly or terribly time-consuming. And never so much so that we ignore common sense and manners.
If the b-day mommies are sooooooo concerned that everything be "fair," then how about this? Let the guests bring a gift for only the child they actually know. If Child A gets $100 worth of gifts and Child B gets $150 worth of gifts, the b-day mommies sort it out
BETWEEN THEM and those two run to
Walmart or Target after the party and let Child B pick out $50 worth of extra crap on
THEIR dime?

That way, they have not demanded that their guests buy a gift for a kid they don't know from Adam and they get to make sure their little angels continue to believe the big lie that everything is fair and even in life.......except it will be at THEIR expense instead of their guests' and that is how it should be. Or how about using some brain power and just not opening the gifts at the party at all, but instead waiting until each kid gets home? Then neither knows "how much" the other one got. (Although you know those two moms are keeping a tally.

)
I stick by what I said earlier. Just because this tacky mother ordered/demanded I bring two gifts does not mean I have to FOLLOW her order/demand. Someone has to stand up and say, (or make clear by their actions) "I don't think so, sister." I'd have brought ONE gift for the child we knew and that's it. Let the b-day moms stew. Who cares if you offend a person who clearly did not care if she offended you?