It's very relative--most people could get that, but on the other hand, if you have on average, say, one 12-hour power outage a year, you spent $10,000 on something you're literally going to use once a year. If the generator lasts 10 years, that's $85 an hour for the use you got from it.In my area, for $10k I can get a natural gas generator that will power my entire house. No batteries, no Span panel, barely a flicker when the power goes out and the generator kicks in.
A battery system might not give you quite as much backup--although it could, depending on size--but it will doing energy arbitrage 365 days a year to lower your electric bill, which depending on where you live, and especially if you also have solar panels, can be a substantial economic benefit.
In my region, for example, power in the middle of the day (when PV is generating) is dirt cheap, but power in the evening can cost 5 or more times that. With a battery, you collect power when it's cheap (whether you generated it yourself or just charge from the grid), then use it when it's expensive.
This may or may not offset the cost of the device over its life, but at least it's doing something for you rather than just sitting there taking up space. Having lived in an area with a lot of outages, and having owned a generator, I can also say that it's a lot easier to sleep with a battery than a generator running, and your neighbors hate you a lot less.