You should told the kids not to accept the toys. If you son is already two, he can do it. He should know(to be teach) that he can only has some toys buy not all he want.
我奶奶佢地都係甘ga...次次見親都買隻winnie the pooh公仔再加其他玩具俾我囡囡...我囡囡而家10個月....但只係winnie the pooh都有6,7隻喇....d玩具都好多,...而家囡囡行街見到d鍾意0既公仔...一到佢手未俾錢已經唔肯放低....唔俾佢掂就冇事..一一拎上手就出事
I don't think it's a problem. Let the grandparents buy them toys and you don't need to buy toys for your children then. Save a lot of money.
Put the new toys in a container/toy chest and let the kids play with them in later periods.
老人家 is like that, accept the toys and everyone is happy. Also I don't think this is the major reason/factor to cause for a kid to be 好現實 in future.