Grandparents gift

Please let me know if I’m being unreasonable because I need outside opinions if I’m being nutty lol

My in laws bought my son (1/1.5 years old) a bike that a toddler can use by walking with their feet.

Automatically, I assumed it was a gift for my son because they said they wanted to buy him something for his half birthday. So the whole time I told my son it was a gift for him.

At the end of the night, I learned that my MIL never intended to let my son take it home…? To play with and whatnot. It was meant as a gift that stays with them and he can play with it when he’s there? And my husband said that my son can learn to ride a bike with them when me (being the more athletically inclined one) wanted to teach my son how to ride a bike. Of course it’s not a real bike so I didn’t say anything.

But is it weird that I feel defensive for my son that he got a gift that he can only use if he’s at his grandparents or am I being selfish?

Sorry guys, I mistyped. My husband said they bought the bike for his real birthday but he was too young so they wanted to give him the bike for his half birthday. They didn’t buy him anything that they could give for his real birthday.

Update: I guess my husband has sided with me because his parents have been talking about ways to get my son to go to their place and buying gifts that he can only have there so he will go over there more. They see him once or twice a week so I guess they’re feeling lonely? To me it was just odd that they would buy him a bday gift that he can only use when he’s there but that’s just me I guess lol