Regarding unusual volume, sometimes I see volume spikes and subsequent price fluctuations but I can't always find the reasoning behind this. I understand earnings and news can cause these spikes but I'm either not finding the correct news sites or there are other reasons.
I can not answer your question in general, but if you look at the TOPS stock on 07/20 then you can see that 1.2 Mio stocks changed hands. This is not really a lot. If I look at the previous volume then I think that one can see that the stock is totally illiquide.
If you look at 1 minute intraday bars on 07/20 then you can see that trading 95,000 stocks in 4 minutes was enough to make the stock go higher by nearly 40 % or 0,5$ per share. I suppose that this move up attracted other people who started to trade the stock.
So the volume may be unusually high, but it is not big. Maybe a trading guru recommended to buy these stocks. Some of these gurus recommend buys afther they bought by themself, expecting higher prices.
The further increasing volume on 07/22-25 may be caused by the original move up by nearly 40%. This attracts people.
You should not generalize things, but you should maybe keep in mind that it is easy to cause big moves in such kind of stocks..