Yes, and Bitcoin has it's own utility. A long term SoV or digital asset. This utility is also bought and paid for when needed. It makes no sense for me to buy Bitcoin if I'm going to need to spend it in the short/medium term.
It is not an ideal MoE/currency.
That is a big reason why many in the third world don't use it and overwhelmingly prefer Tether USDT (Despite what some bitcoiners would like to believe).
Or why it grows increasingly rarer to see Freenet markets solely using Bitcoin to transact. Where privacy+cheap txs are paramount Monero is preferred. Some even exclusively.

All depends how often one gets haircuts and how far out one predicts needing them.
You can get discounts for buying anything in bulk.
It would be more expensive to pay for 1 voucher with Bitcoin every time you need one instead of buying many vouchers to hold and use in the short/medium term.

Most users are onboarding to all crypto thru depreciating fiat. That includes Bitcoin. 
Any crypto can be swapped to and from Monero, that isn't an exclusive privilege of Bitcoin.