Patents are a flawed system. In contradiction of patent law, patents are often given to "inventions" that are obvious, not innovative. Patent inspectors are often not competent to tell the difference. Patents issued to obvious ideas creates an artificial barrier to competition and serves as a tax on consumers and the economy in general. Patents can be useful to incent true innovation, but only if the "burden of proof" of innovation on the applicant is high, and the period of exclusivity is not onerous.
Patent law does specify that obvious ideas are not generally patentable. Otherwise, we'd have to pay license fees for using a wheel.