It sounds complicated, because there are so many popular blockchain networks today, and I'm still confused about the mechanism, how can this happen...
So far I have filled my coin balance to make GAS payment transactions by making purchases on the exchange... yes, this does take a little longer and sometimes I have to pay a withdrawal fee, but my consideration is an old-school consideration where I have to be able to calculate the profit margin if I use gas fees from the exchange....
At least the method I use does not really threaten the security of my wallet... for Getgas, I'm still waiting for further information, because the feature has not been launched.