It could be a good idea, although it's only an assumption on my part since I don't know what kind of shape TNA's finances are, nor exactly what type of financial resources they've got.
That being said, I've not been impressed at all with the vast majority of crowds TNA has been pulling in at their house shows. Whenever I've come across a story on a site that mentions show attendances for TNA and/or WWE, TNA's house show numbers tend to be in the mid to high three digits almost exclusively. Sam mentioned that he went to a show in which TNA pulled in over 12,000 people and that's most definitely the largest I've heard for any TNA house show. However, overall, that big crowd tends to be the exception rather than the rule. TNA's shows in England do pull in much bigger crowds than their shows in the states, so I wouldn't be surprised to hear TNA pull in some pretty good crowds from this tour of the UK.
However, if it's costing TNA more money than it's really worth to put on these house shows over here, then it might be a good idea to stop doing them. When nearly all the house shows pull in less than a thousand people and 1.5-1.9 million people watch you on tv every week in this country, then something needs to be adjusted somewhere.