No, this choice wasn't made due to the lack of gold for dual spec, and no, I don't solely enjoy tanking instances.
Maybe it will sound weird to some, but leveling and questing as protection warrior is a lot of fun. I have been told to have changed my mind as soon as I respec either fury or arms. Been there done that. Not fun. Yes, it can be an entertainment for players who like big numbers to wield 2H weapon (or even two of them) but I am not bothered with slower damage dealing to one mob as long as I can afford dealing it to 10 mobs at once. It's enjoyment of becoming unstoppable killing machine.
To make the fight more fun, I use my cooldowns at all times. It makes caster silenced or interrupted and melee stunned/disarmed most of the fight. It's sweet to not have a single blow/spell land on you during the fight.
Just this.
<3 prot spec ^^