Baha'is are rightfully proud of their principle of "independent investigation of truth"! Why would someone choose not independently investigate these - important and far-reaching - laws prior to accepting their validity? Why follow a law if one has doubts about its validity, especially in the light of being encouraged to investigate it independently?
I obviously disagree about these laws as they might apply to non-Bahai's (for example, in the family), but I'm also interested how Baha'is live them. It's good that a Baha'i can choose how to set up their will - the inheritance laws are not binding commandments then. There are laws regarding prayer and fasting, which I understand are important practices, and binding commandments? How do Baha'is distinguish between the optional and mandatory commandments/laws?
I would say that all Baha'is come into the Faith differently. Truthseeker9 and I both became Baha'is in 1970 and I think the way the Baha'i administration operated back them was different than now. All I had to do was declare my belief that Baha'u'llah was a Manifestation of God and sign a card. I did not know about all the laws back then, just the ones that were basic - prayer and fasting, marriage and divorce laws, etc. The Kitab-i-Aqdas (Book of Laws) was not translated into English until 1992.
Since a Baha'i believes that Baha'u'llah was a Manifestation of God, whose Will is identical to the Will of God, we do not question anything He wrote, and that includes the laws. This of course is the ideal, but that does not mean some Baha'is do not question. However, from my point of view, that would be akin to questioning an infallible God, which is not only illogical but also arrogant. So even if I do not 'like' some laws, I do not question them.
There are no optional laws, all laws are binding upon Baha'is but they do not apply to non-Baha'is.
How well Baha'is adhere to the laws is between them and God and nobody is keeping track. The exception would be if a Baha'i flagrantly breaks a law and brings disrepute upon the Faith; e.g., going to a bar and getting drunk in public and identifying oneself as a Baha'i. In such a case the LSA would talk to that person and their voting rights could be taken away, which is only a worst case scenario. But they would still be Baha'is. As far as I know, only the UHJ can remove Baha'is from the rolls and usually that would be a Covenant-breaker, although it could be for another serious offense.
How well other Baha'is adhere to the laws is not known by other Baha'is since it is a private matter and we do not make it our business what others do or judge each other.