Purchasing a service is no guarantee that it will still exist in the future. It seems to me that a brand-name free provider like, say, gmail.com will probably far outlast the for-pay services that you mentioned.
Compare that with gmail that came out of beta in 2009, belongs to a company that is known for serially shutting down much-used and much-loved services, and whose profitability (that of gmail not google) is not entirely clear.