"makes a person wonder if there could be some big accounts matching the buy ins with selloffs preventing growth."

Market makers is the word you're looking for.

For example CME makes a market for oil, it's a given fact that oil can only move up 7% on a given day, else the market would shortcircuit.

The same goes for any market. Price can't keep going up vertically because you will reach a point where no one is willing to buy anymore, that also means that people can't close their longs (which is technically tring to sell) because there is no one to take over the position.

It's not the chart that is important, it's what happens behind the scenes that is represented on a chart.