I was looking for this too. Thanks!
It is possible to hide columns that are grouped?
Something like:
$("#jqxgrid").jqxGrid(
{
width: 600,
source: source,
groupable: true,
theme: theme,
columns: [
{ text: 'Company Name', datafield: 'CompanyName', width: 250 },
{ text: 'City', datafield: 'City', width: 120 },
{ text: 'Country', datafield: 'Country' }
],
groups: ['Country'],
hidegroupedcolumns: true
});