Nope, if the card is not part of the visa/mc franchise, the vendor has to have an agreement with the issuer. Magnetic strip is insufficient. Go abroad and try using your atm card without a visa/mc logo. Anything that is "pre-paid" is a waste of money. The only benefit is that of occasional convenience - like the example with the kids on a trip above. Example, you are renting an apartment for $1000 a month. You have 12000 in cash you don't need. Two options - prepay the rent for the year so you don't have to remember to make those monthly pmts (now, isn't that convenient?) or invest it and earn interest. Which one do you choose?