Makes Brixton in comparison seem like Mayfair
Shame as would get much bigger audiences if this was showing somewhere with more significance
As fringefan says, theatres serve catchment areas. The nearest producing theatres to the Palace Theatre Watford (except for London, whose population has a good choice of theatres) are the:
Watermill, near Newbury (63 miles)
Mercury, Colchester (76 miles)
Royal, Northampton (52 miles)
So, the Palace is the nearest producing theatre for everyone living within thirty to forty miles in every direction except London, and it would be a significant loss to its catchment population if it ceased production in its location.
The other point is that town centres are very good locations for theatres because they are easily accessible to many people by public transport, and theatres in town centres are highly visible to large general populations who reside and work in the immediate vicinity.