Yes, most Highstock features can be applied to standard charts. From a licensing point of view, using features of the Stock package obviously requires a Highstock license.
Technically Highcharts Stock is implemented as a set of plugins for Highcharts. The entire code base for Highcharts is included in the Stock package, and you can invoke a chart using Highcharts.Chart and enable certain features that are normally associated with a stock chart.
Examples:

Using flags in Highcharts
Enabling a scrollbar in Highcharts
Gap size in Highcharts   _{Your Comment}