What kind of gaming expo? Our family is big into Tabletop Gaming! We go to Origins Game Fair every year (one of the largest board gaming conventions in the United States).
You absolutely should go to Mass while on vacation. Let me rephrase that, you get to go to Mass while on vacation : )
No matter where we go on vacation, we try to find the nearest Cathedral. It is neat to see and compare them.
When we visited Cozumel, we go to attend a Church where the first Mass was celebrated in Mexico! How cool is that?!
Other times we have visited Basilicas and that has been an experience too.
Going to Mass should always be a part of your Holiday. The very word Holiday comes from the phrase Holy Day. God has blessed us with this life and it is right and just to remember Him while we are on leisure/island time (when possible).
I say, make it fun. Make it an adventure. Don’t see it as something you are obliged to do, but something you want to do.
I love your Mom, but she is wrong on this one : )