In SV terms that's what? A round B series?
Sure, maybe the debts are substantial, but that seems like it was cheap.
Further driving down the value (which does seem to be cheap given that GH made 54M profit out of 914M revenue) are long-term obligations: lease agreements that may be expensive to break, employment contracts for the drivers and operating costs (fuel, road tolls) that have to be paid even if a bus line isn't operating at capacity (or, as with corona crisis, at all).
Greyhound seems like the kind of iconic US company that would pique the interest of Berkshire Hathaway -- it is telling that BH didn't pick it up.
As for being "iconic", I'm not sure "iconic" is the word I'd use to describe Greyhound. It has a reputation for sure, but not a good one.
I knew it couldn't be correct after half a second of reflection, but it's a measure of how "iconic" Greyhound is.
Also, they have big real estate (often in beautiful old buildings) in the center of the big cities, and their branding is red white & blue.
It seems likely that they don't own the real estate, and maybe the cities own the bus stations which only appear to be operated by Greyhound. I have only been inside about half a dozen bus stations though.