It really depends from country to country and card companies:

Countries are enforcing regulations on financial institutions: KYC (Know Your Customer) and AML (Anti Money Laundering) - which when applied to disposable cards make them impossible to use in the same way you can't use them to transfer money to anyone's personal account

Second issue is fraud and chargebacks - as explained here: Why is Bitcoin so susceptible to credit card fraud?

Third issue is TAX. Taxman wants to know how much money you have on your bank accounts and that is impossible with bitcoin, unless they can track transaction when you bought it.

Dutch taxman is asking you to report if you have bitcoins, and in Holland you can buy them using Dutch money transfer system (IDEAL). If you live in England you can buy them from EU bitcoin exchanges/sellers but you need to execute SEPA transfer from your bank which may take few days to clear.

It all kind of depends on where you live (in terms of legality), and what purpose you want out of buying with a disposable/personal debit card.

I can say in the US, in order to buy bitcoins you can't reside in NY because of the laws there. You can read more here along with the other countries legality issues: https://en.wikipedia.org/wiki/Legality_of_bitcoin_by_country#United_States

Also for the US, North Carolina seems to be having trouble with sites like xapo: http://www.newsbtc.com/2015/07/16/bitcoin-services-provider-xapo-no-longer-operating-in-north-carolina/

As for just buying in general, if you'd like to purchase in cash I prefer using localbitcoins.com. That's where I generally go to purchase bitcoins because I like the anonymity of it and don't have to deal with exchange sites as much and having to link my bank account in any way. The prices are a little higher than what the base price of bitcoins are, but the price of convenience (for me) is worth the extra up charge.