Unfortunately, and I do sympathise with you, yes. At times mutually agreed. If a property that's intended to be let after you've moved on, it's perfectly reasonable for any landlord to want a seemless switch. Or he loses income. We were lucky with two rentals - the first was being sold, and given the circumstances at the time, we said ok to external photos being taken, but no to showing until after we left which was fast as we found another property to rent. With another, the owner was wanting back in herself, so there was no need for showing.
It would of course, depend on local laws, and the terms of your Lease re your rental, but it's quite normal to expect the owner to want to show the property with an ongoing rental situation. You don't need to be there (except I would if my furniture etc. was in the property - potential for theft) however. But you are entitled to expect viewings by prior arrangements. Not just people dropping in.