If the Purchase Contract (in California) shows you as a contingent buyer (CAR Form COP) and the seller and you agreed to a 72 hour first right to perform, then without question they can still have an open houses and recruit offers.
If you have no Real Property to sell before you can buy (your purchase contingent on the sale or you property) then I would question if this activity was contractually agreed to. Even is this market today (S. Cal) I would question a listing agentâ€™s motive for having an open house that my client (buyer) would soon own. Not saying is illegal because it isnâ€™t but I would request the activity to stop.
Lastly, the listing agent has a fiduciary to the seller to obtain offers (Backup, Options or otherwise) until funding and recording has completed. If, as the listing agent, we got an offer without contingencies, then I would list the property on the MLS as â€œBackupâ€ and continue to allow agents to show it to buyers. However, I would not conduct open houses. Remember, opinions are like noses most all have one.