No, you CAN NOT buy citizenship in Switzerland, not even in Zug. You can however get a permit to stay that is renewed every year, if you're wealthy (defined as:

No, you CAN NOT buy citizenship in Switzerland, not even in Zug. You can however get a permit to stay that is renewed every year, if you're wealthy (defined as: sustain life here without the need of work). The threshold is way lower than 5 million and is decided case-by-case.