I am pretty new to Bitcoin and exploring the stuff. Able to understand how difficult is to mine new coins.

Recently came to know about Bitcoin Burning (it seems opposite to mining). Checked some of those burn addresses in blockchain explorer and found 'even in 2021' they are receiving Bitcoins. With Bitcoin price being so high now a days, why people are burning the coins instead of spending for themselves?

At some place read that people are burning the coins for fun (which I can't believe).
Instead of burning, people can spend the coins themselves or send to their friends/relatives.

Some burn addresses are having more than 100 BTC. (Being a late starter, even a hundredth of BTC is a very distant target for me)
1CounterpartyXXXXXXXXXXXXXXXUWLpVr (2130.93142654 BTC)
1ChancecoinXXXXXXXXXXXXXXXXXZELUFD (480.19566656 BTC)

I am not giving any kind of advice not to burn. I am just being logical and trying to understand reason behind burning.

Or is Bitcoin Burning useful in any way? Am I not understanding the Bitcoin concept completely yet?