I don't think there is anything strange about it, because BTC is widely accepted and you know that. Even you, it's more likely that the first cryptocurrency you used was BTC, so it shouldn't be a surprise. We didn't know about these altcoins before, BTC was first and it was like the main thing that is called cryptocurrency. If you go out there, even people that don't make use of Bitcoin, if you ask them questions like - do you know what is called cryptocurrency? They will answer you Bitcoin and not Ethereum, not Bitcoin Cash, not even ripple or any other. That's not going to change easily, it's just how it is.
Bitcoin is widely accepted and that's what everybody wants to use. Just like you, all the people I have worked with only want to make payment with Bitcoin. I'm still looking for ways to test out other cryptocurrencies like Ethereum and see how they work, but nobody needs them.
After the acceptability of bitcoin is the trust the coin. Trust in the safety of transaction, in the size of community and the system as a whole with soft disposition to bitcoin in particular by governments. The next in this line will be the stable coin and seeing government support in stable coin especially in USD value could scale up in few years from now. Bitcoin is widely accepted and that's what everybody wants to use. Just like you, all the people I have worked with only want to make payment with Bitcoin. I'm still looking for ways to test out other cryptocurrencies like Ethereum and see how they work, but nobody needs them.
