Yes, you are wrong. Let me explain again:
People use Western Union in emergencies--like being stranded halfway across the country with no money for gas, that sort of thing. The kind of emergencies in which Bitcoin would be of no use, since it can not be spent in in the podunks where these emergencies take place. Gas stations don't take Bitcoin.
If you are talking about needing something which could be bought online, simply ask the person to put the purchase on his CC, and save bot of you the fee and the hassle.
But I can also pay for someone's gas in the middle of nowhere instantly from my living room with btc, all they need is the payment protocol.
Wait, wat? We're not discussing hypotheticals, we're talking IRL. Today, most (if not all) gas stations don't take BTC.