Other than this picture to the left of Gussie with a new ebike, the content below is with respect to non-motorized fat tire bikes.
Electric fat bikes take some getting used to, as I'll explain soon. But Gussie needs a walk.
This picture is a recreation. There's a dropoff here, it's usually packed with snow. Well - the snow softened, my tire augered, turned sideways, and I ended up in the spot I shot this pic. It was kind of fun - I actually shot a phone pic at the time. Point is - you can come off the bike, but most landings are in soft snow.
When you're riding on packed single track, you sail along unimpeded. But if your tire goes an inch or two off the track, you're done.
Getting out of these conundrums can sometime be comical, like getting stuck in powder when skiing. In flat areas, where first timers will go, the side of the track isn't so deep and challenging.
After you've dug yourself out and have the bike back on the single track, you only have 20 inches to get on the bike, hop on and get it rolling (without going an inch off the track and burying yourself again - it happens).
I get asked that all the time.
On plowed concrete, it all depends on recent weather. If it'd cold and there's new snow, it can be glorious. But if there's been sun, thawing, followed by a temperature drop and an inch of snow - watch out! Smooth ice under an inch of snow is dangerous, in fact, it's the biggest danger out there.
On snow... well, it depends on the snow. If it's packed nice, and the temps are cold, the fat tires are grippier than tires on dirt. At the other end of the spectrum is slush. It can be impossible. But it's extremely unlikely you'll see slush.
New snow on the trails? If there's four new inches on previously packed, flat terrain - it's like it's not there. Six inches, a couple degrees downhill, it's just as nice. If you add a few degrees uphill, or more inches than I've noted - it can get progressively more difficult, and requires more energy.
If there's too much snow, maybe skiing is the right choice!
For some reason, people think it is difficult to ride a fat bike. If the guy shown here can ride this bike, anybody can.
On hard ground, it's like riding a bike. And, it's not as heavy as you'd think. Well, the Surly and the kid's bike are a little dense. The Specialized is so great to ride, it's my #1 bike all year. You can lay the tires on edge and make turns a regular bike just can't handle. It almost feels like skiing.
I've been standing in snow and asked that question. Aside from the obvious, fat bikes are fun. You can make looping turns and go places a normal bike can't.
I don't mean tearing up a forest between trails - that would be bad. It's places like the rocky shore line of Lake Dillon. On a normal bike, it's not much fun. On the fattie, it's another place you can go without a lot of other people.