$30 was more meaningful at one time in Massachusetts. For the unmarried that is maximum fine for fornication. Commonwealth law Chapter 277: Section 39 defines that as "Sexual intercourse between an unmarried male and an unmarried female."
That seems to let homosexuals off the hook. Also, apparently if either offender is married, he or she hops from fornicator to adulterer.
However, the penalty for being convicted is not too onerous.
Chapter 272: Section 18 Fornication
Whoever commits fornication shall be punished by imprisonment for not more than three months or by a fine of not more than thirty dollars.
One must wonder how flagrant the violators would have to be to face this charge, and whether anyone enforces this law today.