What point would that be? As has been said...there is very little wrong with the picture as a temporary shelter. People do things like this all the time as a means of quarrantining new animals, as well as simply a matter of temporary housing.
As long as temperatures are monitored and the snake is eventually moved to a proper enclosure...what is wrong with it, and what, exactly, is double het's point? The O.P. already knows that the enclosure isn't perfect, and already knows that they will need to get a proper enclosure ASAP...so...what, exactly, is the point in coming online and making somebody feel like crap for absolutely no reason?
There is no danger in the setup as shown, as long as temperatures are monitored, and not allowed to get too hot. In fact...it is one recommended way of temporarily housing snakes in the book, "Cornsnakes in Captivity" by Don Soderberg. Is double het. gonna come on here and tell Don S. that he is an idiot for making such a recommendation, and that he needs to do some research before getting a snake?
The bottom line is, quite simply, that double het acts very rude and condescending in his replies. That is uncalled for. ESPECIALLY in a situation such as this where there isn't ANYTHING about the original post that indicates an immediate danger or lack of research on the part of the original poster. It may not be ideal, and it may not be the way double het would LIKE it to be done...but there is nothing immediately dangerous or inherently wrong with the setup, providing the O.P. monitors the temperatures.
In other words...double het. does NOT have a point, other than to make people feel inferior and to act like an arrogant...YOU fill in the blank...