I am not a parent, but if I were I would not want to walk down the street with my kids alongside naked men and women, that would be my choice as a parent.
Other parents may make different choices. Nudist groups are filled with whole families, kids, parents and seniors, which is a choice they make without infringing on my rights. They may be made uncomfortable if I chose to stroll through their private beach or park fully clothed. Parents make the choice for their own children and we would not think about forcing a parent to make decisions about how to raise their own children.
For most of recorded history we as a society have agreed on certain "social norms", and limited certain behavior to closed areas. Just like children are not allowed in strip clubs, or into movies that show nudity (without a parent/guardian), we limit natural acts, such as sex in public. These are legally defined as lewd acts and every society can freely arrive at what lewd means. Historically, the definition has changed and will continue to change.
Nudity, engaging in sexual activity, urination or defecation (by individuals capable of accessing a bathroom) and other normal human activities which have been deemed to be private by thousands of years of established social decorum are acts best left for private places, where no one else is forced to observe.
From what I have seen, heard or read about, the complaints against nudity are not coming from Macy's, or office buildings in the financial district or the quiet neighborhoods of the Sunset or Richmond. The nudists seem to be limited to a block or two of the city. Would it be that much of an infringement of rights to request that it be further limited to a private backyard or club?
Since a nudist has plenty of opportunity to be nude in private without being disturbed by the clothed, they need not force their behavior on others. Some things are best left private.