It really depends on what they ascertained their needs as. Perhaps they don't feel they need the additional protection, or they have another backup scheme in m

It really depends on what they ascertained their needs as. Perhaps they don't feel they need the additional protection, or they have another backup scheme in mind. If their solution works for them (which is seems to) then indeed, for their needs at least, the cost comparison is pretty accurate. It might not add up the same for your needs (assuming you want multi-data center redundancy of all data, etc...).