Yes, I also use the bubble tea straws in my bottom tier and regular straws in the upper tiers.
Some of my cakes are moved out to the beach or to a tent after being set up in the foyer of the resort.
When I put the cake together, I hammer one
sharpened 6 to 7 inch wooden dowel down in each of the top tiers. That way the 6 is connected to the 8, and the 8 is connected to the 10 and the 10 is connected to the bottom tier. It is much easier to take apart that way. I put the dowels in "off center" so I don't run into the others.
This is just one way of doing it that works really well for me!