I have a technically 'better' bike than my fattie. However, I only ever seem to sit on and ride the fattie. The smiles-per-mile is the clincher for me. I ride for physical fitness and mental health (endorphins). There's no snow or sand here but the fatbike ticks every box for me on every ride on the urban streets in my neighbourhood: physical wellbeing, mental wellbeing, more calories burned per ride compared to my hybrid, feel-good factor, kinder road users who don't harass me on the streets, thumbs up from so many people whilst out cycling. What's not to like?
And like a previous poster, I use flat pedals and just my regular gym shoes so no special footwear or clothing is required.