Is it me or is this not a normal play date activity?

[ButterflyBitch]

My son has been on a play date recently where he and his friend where sucking helium out of birthday balloons. He’s not quite 10.
Is it me or if this odd?
I’ve googled and think it won’t cause harm but it’s not ideal is it? Just a bit baffled that on a normal after school play date this was one of the things they did.
I don’t know whether to mention to the mum or not that I’m not overly happy about it.

[kateandme]

me mum and dad did it when i was about that age with leftoever birthday balloon.really fun!

[kateandme]

i dont think its a deff danger as such.but something one the off chance can go wrong.so your are putting yourself in a bit of risk.

[Rangeloaf]

I’m just perplexed at all the posters declaring it THE BEST FUN and such. Surely it’s just mildly amusing for 20 seconds? You need more real fun in your lives!!