Why waste that time and mental effort to save literal pennies? Isn't your limited time alive on this incredible earth worth more? This is like driving the whole afternoon around town to find the cheapest gas.
I agree, I started this way to test it out and just kept doing it. Although it saves 65€/year, not pennies. And I'm in Europe so I don't earn nearly as much as the average American engineer.
I would still select the search engine for a number of queries though. I find Google better for local stuff, use WolframAlpha for computations, and Perplexity for LLM answers.
Google Maps is the undisputed king for local results. Not even Apple has any chance of contending that throne, much less Kagi. My prediction is that maps will become the core of Google's search business quite soon.