I am on the fence about backups.
I can see average customer expecting it or pointing to multitude of companies that include backups in their plan.
See I can go from provider to provider and see all the usual brag points about super network and giant routers and Fort Knox style secure facility. Every provider basically mimics the others as this is the "base" point of entry in their mind to be selling in this industry.
Backups are just a part of the "base" point of entry if you are playing competitive.
Look in relative coverage here.... ChicagoVPS - had backups, multiple time failure with those... Either didn't have them or no integrity checks going on. RamNode, they revised their plans to not have backups as of July. Market sentiments about that drop of expected feature, people aren't thrilled.
At end of the day, customers expect their services to work. Imagine the electric utility grid down because they didn't have redundancy. Imagine your water polluted because of mass filtering failure. Data, your data is the commodity one continues to be drip fed as the service. When that fails, customers have choices. Since a VPS provider doesn't monopolize right of way, exclusive path to the home/business/customer that customer has MANY options, many of your competitors gladly will eat your lunch, take your customer and punt you in public about it.
All that said, backups cost money. Must rack spare storage / server(s) to accomplish this and ideally some method of shipping copies secondary backup off site just in case something were to obliterate that datacenter / your rack.
Build the redundancy into the plans. Build the cost into the customer invoice amount.
If you are cheap / lean, then offer backups as a paid addon to customers.
Believe me when I say this problem isn't just one cheap VPS companies have. Plenty of $20+ per gigabyte of RAM VPS shops that aren't telling the truth / do not have backups, even though their sale stuff lies about it.
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