Even if they are viable, it would eat into profit significantly. It's a trade-off between customer happiness and profit. The reality is that even when a large number of customers are occasionally unhappy, they may still not leave the company/product for various reasons. Companies then choose to accept that custom unhappiness since it does not impact their revenue enough practically. Arguably, they have an obligation to make that choice. It's the "best" thing for the company, at least in the shorter term.