Yes, it is possible for an attorney to waive the appearance of his/her client at court dates. And, while an attorney is not going to say, "I'd like a continuance so I can make sure I get paid," I'm not going to tell you that it doesn't happen. There are all sorts of legitimate reasons a continuance can be needed and requested for.
This response is for general purposes only and does not establish an attorney-client relationship. You should contact an attorney to fully discuss your issues.
While legally the defense attorney can waive his clients appearance, in certain jurisdictions or with certain judges it is frowned on. To answer your second question, it has and can happen but most lawyers would not give that as a reason, rather they would just ask for a continuance.
The answer is dependent on the practices in that county. Typically, a lawyer can waive the presence of the client for status conferences as it is permitted by the Florida Rules of Criminal Procedure. The lawyer must seek approval from the client to ask for a continuance which effectively waives the client's speedy trial rights. An ethical lawyer should not be continuing a case other than to properly prepare the defense and not to make sure he/she gets paid. Better communication is needed between the lawyer and the client so that each person's expectations are being met and the client's rights are not compromised.