So I cannot believe you all are fighting over a little bit of beach. . .lol. Also I am always amazed that people build on top of each other. There is a whole map of perfectly acceptable building spots, yet you two are built right up against one another.
To answer your question, no it is not against the rules, but spamming fences or foundations IS against the rules.
You can submit a report on them for foundation spamming here.
https://funcom.zendesk.com/hc/en-us/requests/new
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