Probably not. CO2 is relatively inert.

I can't answer the OP's question (is CO2 easier to bottle than air), but do agree with post #3... CO2 molecules are smaller than the N2 molecules that comprise 78% of "regular air", so they leak out of your tube quicker.

Bonus: Since most of what leaks out of a tube aired up with a regular pump is O2 and other small gases, over time you should have a tube containing almost completely nitrogen, which should stay at the desired pressure for longer.